[Support request] Customizer Error 500

Hello,

I installed GeneratePress on my site. When activated GP Premium the Customizer returned an error:

Fatal error: Call to a member function check_capabilities() on a non-object in /home/vietanh/domains/truongvietanh.com/public_html/wp-includes/class-wp-customize-control.php on line 281

Deactivated GP Premium and customizer back online.

My site information:

### wp-core ###

version: 4.2.10
site_language: en_US
user_language: en_US
permalink: /%postname%/
https_status: false
user_registration: 0
default_comment_status: open
multisite: false
user_count: 5
dotorg_communication: true

### wp-paths-sizes ###

wordpress_path: /home/vietanh/domains/truongvietanh.com/public_html
wordpress_size: loading…
uploads_path: /home/vietanh/domains/truongvietanh.com/public_html/wp-content/uploads
uploads_size: loading…
themes_path: /home/vietanh/domains/truongvietanh.com/public_html/wp-content/themes
themes_size: loading…
plugins_path: /home/vietanh/domains/truongvietanh.com/public_html/wp-content/plugins
plugins_size: loading…
database_size: loading…
total_size: loading…

### wp-dropins (1) ###

advanced-cache.php: true

### wp-active-theme ###

name: university (university)
version: 1.9.8
author: CactusThemes
author_website: http://themeforest.net/user/cactusthemes
parent_theme: none
theme_features: custom-header, custom-background, editor-style, automatic-feed-links, woocommerce, post-formats, menus, post-thumbnails, widgets
theme_path: /home/vietanh/domains/truongvietanh.com/public_html/wp-content/themes/university

### wp-themes-inactive (2) ###

GeneratePress: version: 3.0.2, author: Tom Usborne
Twenty Fifteen: version: 1.1, author: the WordPress team (latest version: 2.8)

### wp-mu-plugins (1) ###

Health Check Troubleshooting Mode: author: (undefined), version: 1.7.2

### wp-plugins-active (8) ###

Akismet Anti-Spam: version: 4.1.2, author: Automattic
Call Now Button: version: 0.4.0, author: Jerry Rietveld (latest version: 0.4.1)
Display PHP Version: version: 1.5, author: David Gwyer
GP Premium: version: 1.12.3, author: Tom Usborne
Health Check & Troubleshooting: version: 1.4.5, author: The WordPress.org community
Insert Headers and Footers: version: 1.4.5, author: WPBeginner (latest version: 1.5.0)
PHP Compatibility Checker: version: 1.5.0, author: WP Engine
WPBakery Visual Composer: version: 4.4.3, author: Michael M – WPBakery.com (latest version: 5.0.1)

### wp-plugins-inactive (31) ###

301 Redirects: version: 2.52, author: WebFactory Ltd (latest version: 2.53)
a3 Lazy Load: version: 2.3.2, author: a3rev Software
Countdown Timer Ultimate: version: 1.2.4, author: WP OnlineSupport (latest version: 1.3)
Duplicate Page: version: 4.0, author: mndpsingh287 (latest version: 4.3)
Duplicator: version: 1.3.36, author: Snap Creek (latest version: 1.3.40.1)
EWWW Image Optimizer: version: 2.8.0, author: Shane Bishop
Infusionsoft Landing Pages: version: 1.3, author: Infusionsoft & David Bullock
Infusionsoft Official Opt-in Forms: version: 1.0.5, author: Infusionsoft
Lazy Load for Videos: version: 2.8.7, author: Kevin Weber
MailMunch – Grow Your Email List: version: 3.1.1, author: MailMunch (latest version: 3.1.2)
Mega Addons For WPBakery Page Builder: version: 4.0, author: Nasir (latest version: 4.2.6)
Nofollow for external link: version: 1.2.2, author: CyberNetikz (latest version: 1.2.3)
OneSignal Push Notifications: version: 1.17.9, author: OneSignal (latest version: 2.1.4)
Pixel Cat Lite: version: 2.4.2, author: Fatcat Apps (latest version: 2.5.5)
Post Views Counter: version: 1.2.14, author: dFactory (latest version: 1.3.3)
Q2W3 Fixed Widget: version: 5.1.9, author: Thomas Maier, Max Bond
Recent Posts Widget Extended: version: 0.9.9, author: Satrya
Revolution Slider: version: 4.6.5, author: ThemePunch
Shareaholic – Grow and Engage Your Audience: version: 8.13.5, author: Shareaholic (latest version: 9.5.0)
University – Shortcodes: version: 1.9.8, author: Cactusthemes
University Course: version: 1.9.8, author: Castusthemes
University Event: version: 1.9.8, author: Castusthemes
University Member: version: 1.9.8, author: Castusthemes
University Project: version: 1.9.8, author: Castusthemes
UpdraftPlus – Backup/Restore: version: 1.16.16, author: UpdraftPlus.Com, DavidAnderson (latest version: 1.16.43)
WordPress SEO: version: 2.2.1, author: Team Yoast
WP-PageNavi: version: 2.93, author: Lester ‘GaMerZ’ Chan (latest version: 2.93.3)
WPBakery Visual Composer WHMCS Elements: version: 1.0.2, author: VOID CODERS
WP Floating Menu: version: 1.2.9, author: AccessPress Themes (latest version: 1.4.2)
WPFront Notification Bar: version: 1.7.1, author: Syam Mohan
WP Rocket: version: 3.2.3.1, author: WP Media

### wp-media ###

image_editor: WP_Image_Editor_GD
imagick_module_version: Not available
imagemagick_version: Not available
gd_version: bundled (2.1.0 compatible)
ghostscript_version: not available

### wp-server ###

server_architecture: Linux 2.6.32-504.23.4.el6.x86_64 x86_64
httpd_software: Apache/2
php_version: 5.4.45 64bit
php_sapi: cgi-fcgi
max_input_variables: 1000
time_limit: 120
memory_limit: 256M
max_input_time: 120
upload_max_size: 512M
php_post_max_size: 512M
curl_version: 7.19.7 NSS/3.19.1 Basic ECC
suhosin: false
imagick_availability: false
server-headers: unknown
htaccess_extra_rules: true

### wp-database ###

extension: mysql
server_version: 5.5.31
client_version: 5.0.10

### wp-constants ###

WP_HOME: undefined
WP_SITEURL: undefined
WP_CONTENT_DIR: /home/vietanh/domains/truongvietanh.com/public_html/wp-content
WP_PLUGIN_DIR: /home/vietanh/domains/truongvietanh.com/public_html/wp-content/plugins
WP_MAX_MEMORY_LIMIT: 256M
WP_DEBUG: false
WP_DEBUG_DISPLAY: true
WP_DEBUG_LOG: false
SCRIPT_DEBUG: false
WP_CACHE: false
CONCATENATE_SCRIPTS: undefined
COMPRESS_SCRIPTS: undefined
COMPRESS_CSS: undefined
WP_LOCAL_DEV: undefined

### wp-filesystem ###

wordpress: writable
wp-content: writable
uploads: writable
plugins: writable
themes: writable
mu-plugins: writable

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